In the related art, heat treatment devices including a heating chamber and a cooling chamber are used in order to perform treatment such as quenching or the like on a metal part serving as a treatment object. For example, Patent Document 1 discloses a heat treatment device in which a plurality of heating chambers are provided above an intermediate conveyance chamber, and a cooling chamber is provided below the intermediate conveyance chamber. In the heat treatment device disclosed in Patent Document 1, a push device made of a cylinder mechanism is used in order to perform delivery (conveyance) of a treatment object between the intermediate conveyance chamber and the heating chamber. Specifically, the treatment object is conveyed to a front heating chamber by placing the treatment object on a disk-like tray (a conveyed body), and pressing the tray with the push device to push out the tray in a horizontal direction.
Additionally, Patent Documents 2 to 4 also disclose a heat treatment device that conveys a treatment object by pressing the treatment object with the pusher device.